Jackson’s film, originally released in 1994 and currently reissued on Blu-ray and remastered DVD, sticks closely to the facts of the case – the murder scene was even shot on the same forest path where the real crime took place. However, Jackson famously didn’t film in the exact spot of the murder, after the forest went eerily quiet.

Juliet Hulme (Kate Winslet) moves with her upper-class English parents to Christchurch, New Zealand, after having traipsed around various bits of the British Empire as a young girl. She joins a new school and quickly forms a friendship with Pauline Rieper (Melanie Lynskey). Bonding over “the world’s greatest tenor” Mario Lanza, a strong imagination, and because they were both sickly children, the 14-year-old girls fall into an intense romantic friendship and immerse themselves in creating a fantasy world populated by queens, kings and lovers, in which an elaborate intrigue develops involving murder, love and sex.

Meanwhile, Pauline, who is from a working-class family and also a typical teenager thinking her parents don’t “get” her, fantasises about cutting off her own parents and living in Juliet’s apparently charmed world, practically moving into her new best friend’s house.

Jackson displays his usual virtuosity with special effects. He took the amazing creativity from his earlier horror comedies, like Bad Taste, and put it to good use in representing the imaginary world and psychology of these teenage murderers.

From plasticine models of the characters in Juliet and Paul’s epic story, we trip into a full-sized plasticine world of castles and dancing characters. Particularly convincing is the scene when the girls go and see Orson Wells’ The Third Man; Juliet has worked them both up into a hysterical fear of Orson, which they get enjoyably caught up in, believing he is chasing them home from the cinema.

When their parents decide the girls’ friendship is “unhealthy”, aided by a “diagnosis” of homosexuality by a psychologist, the decision is taken to split them up, with Juliet to be sent to live with distant relatives in South Africa. To forestall the event, the girls cold-heartedly plot to murder Pauline’s mother.

The film takes a situation which is unimaginably horrific and helps the audience see two perpetrators as humans, without excusing what they did

During the real-life trial in 1954, a lot of hysteria was kicked up in the press over the girls’ lesbianism and the decline of morality – suggesting that the sheer intensity of their romance somehow led them to committing matricide. Meanwhile, some have argued that Heavenly Creatures just replicates the cinematic trope of killer-lesbians or psycho-lesbians .

Teenagers committing murder has become a genre in an unto itself (from Heathers to Secret History), testing and representing adult culture’s fear of young people.

Stories of teenagers, who tend to be (partly self)alienated from adult society, committing murder somehow manage to reflect these adult fears and yet, as they are aimed at a young audience, they are pitched as relatable enough to act as a catharsis for the drama of being a young person. Notably, Winslet and Lynskey were the same age during the filming as the characters at the end of the movie.

In the search to explain how something so horrific could happen, that two teenage girls could conspire to murder one of their mothers, people reach out and try to pin it on something. The girls’ sexuality or their immersion in an imaginary world makes for an easy target.

That’s clearly what happened in the aftermath of the real case; however, Heavenly Creatures, co-written by Fran Walsh and her husband (Peter Jackson), starts off getting us to sympathise with Paul and Juliet.

The film takes a situation which is unimaginably horrific and helps the audience see two perpetrators as humans and understand them, without excusing what they did. In fact, both the murder itself and anti-mother sentiment permeating the film were pretty horrifying to me at the time I first saw it, because it was only a year or two after my own mother died.

Rather than representing them as inherently evil sociopaths, as the press did at the time of the murders, Jackson and Walsh went back to extensively interview people who had known the girls and also read Pauline’s diaries that feature in the film.

In the resulting film, the focus is on what are some hardly uncommon experiences for teenage girls: being angry and upset with your parents, inability to relate to adults, constructing imaginative worlds (although this feels to me like something from younger childhood), and intense romantic relationships with other girls.

It might be worth asking: who or what is the “monster” here? Is it a manifestation of the extremes of the condition of being a teenage girl?

Rewatching the film as an adult, I wasn’t able to muster much sympathy for their melodramatic and over-the-top viewpoint – how many minutes of this film are taken up by weeping?!

But I feel like I also have to leave space in this review for how I used to feel about this film as a teenager, by which I mean I loved it. We, the teenage audience of Heavenly Creatures, were sucked into the fantasy world with the actresses, and also into the intense romantic friendship/relationship that developed.

The film, which draws on the same materials as previous accounts – the transcripts of Pauline’s diary produced for the trial, the reports of the defence and prosecution psychiatrists – succeeds where other analyses have failed precisely because it portrays this relationship not as pathological, but as the freaky end of a normal continuum.

Heavenly Creatures is much more disturbing than something like Heathers, because that film had a hero character: Winona Ryder flirts with some extremely dark shit, and with Christian Slater, but ends up clicking firmly back to reality once the murdering begins, and deciding she’s not a sociopath. Which, despite adult worries, is what the audience of young people could also relate to! Heavenly Creatures doesn’t have an ‘out’ like that; there is no hero, both the girls commit a horrific, horrific murder.

Because this is a Peter Jackson film, it might be worth asking: is this not just a horrific film, but actually a horror film? If so, who or what is the “monster” here? Is it about how the monstrous act of matricide was committed by two frighteningly relatable teenagers?

Or is the “monster” a manifestation of the extremes of the condition of being a teenage girl?

Addendum, or disturbing facts about the real-life crime:

Juliet Hulme changed her name and went on to become a relatively successful author of historical detective books. Meanwhile, when Pauline Parker sold her house in the 2000s, these drawings were found.

@Laurel, Yeah, I read that, but didn’t want to get into it…. that’s partly why I was using the phrase “romantic friendship”…. but also, the film version draws heavily on Pauline’s diaries from the time.

Even though I’m a writer, I remember very little of the words or plot of films. Instead, I tend to take away images and feelings.

I remember thinking the film did a remarkable job capturing the unsettlingly intense friendships that can grow between teenage girls. The sexual exploration in the film didn’t strike me as nearly as significant as the emotional enmeshment, and actually felt a bit false to me.

When I think of the film, I see the final scene where they are walking with the mother through the woods, all those footsteps, and the rising panic and determination, and how it takes several strikes for them to kill her, which just made it all the more gruesome. I remember being shocked by it and also understanding their behavior, because society had thwarted them in the midst of such a serious attachment, at a time in their lives when such events and friendships can really feel like life or death, like the world is ending, if you are a desperate child to begin with.

Admittedly it’s years since I saw this film, but as far as I can recall the only reference to a sexual relationship between the girls comes when the Psychiatrist “diagnoses” them with homosexuality, and it’s then dismissed.

For me the horrifying thing was the fact that they were very relatable characters and blurred the line between protagonist and villain, and the dismissal of sexuality in their relationship aided this, making them appear to be more like desperate people who made a bade choice than crusading freedom fighters. The murder scene in this film is the most horrifying I’ve ever seen.

The pleasing thing about this film is that it’s one of only a few that portray the inner thoughts of female protagonists; there are many that do this for men but I struggle to think of ones that do this for women which aren’t romantic comedies.